Viscoelastic and conductive characteristics of titanium carbide/polyethylene composites in relation to their structural parameters

摘要

Titanium carbide (TiC)/polyethylene (PE) composite is a candidate for a positive-temperature coefficient resistor, which is used for a self-recoverable element that provides protection from overcurrents in many kinds of electrical devices. In the present study, the PE-based composites containing various volume fractions (phi) of TiC were prepared, after which their viscoelastic characteristics were investigated compared against their electric conductivity as a function of temperature. When the value of phi exceeded 0.39, the resistivities of the sample decreased steeply with increasing TiC content. The resistivity of the specimen maintained a constant value of about 0.1 Omegacm in the range of phi values > 0.52. Alternatively, the changes in the storage moduli at room temperature with various phi values of the samples could be expressed by a modified Kerner equation with the maximum phi value of 0.67. Melting behaviors of the samples were also examined and discussed in terms of their morphological features. (C) 2004 Wiley Periodicals, Inc. [References: 11]